Don't call it a wagon—or, maybe you should. Porsche has taken the wraps off of the first true body style evolution of its Panamera flagship, a five-door wagon-like hatchback that the German automaker says improves the model's load-carrying ability without diminishing its performance. The car made its public debut at the Geneva auto show.

It's called the 2018 Panamera Sport Turismo and it will be available in Panamera 4, Panamera 4S, Panamera 4 E-Hybrid, and Panamera Turbo configurations in the United States. Despite its unique rear end, the Sport Turismo shares the same 116.1-inch wheelbase and 198.8 overall lengthy as the conventional model. The difference is in how the Sport Turismo uses its girth aft of the B-pillars. Its rear doors are the same length, but their tops curve a bit differently to reflect a more bulbous roof pillar at the rear.

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A special roof spoiler that adjusts automatically increases downforce to compensate for the Sport Turismo's modified curvature. 

Styling aside, the Sport Turismo should mostly drive like its regular Panamera siblings. Porsche says to expect the same performance figures from a lineup that ranges from a 330-horsepower, 3.0-liter turbo V-6 up to a 550-hp twin-turbo V-8. All models will direct power to each corner since all-wheel drive is standard. 

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But the Sport Turismo isn't necessarily about adding to the Panamera's impressive performance envelope. Instead, it includes an extra seat in the rear, making it the first five-passenger Panamera. That rear bench folds in a 40:20:40 configuration. Porsche says it will also offer the Sport Turismo with two power-adjusted seats in the rear like the standard Panamera. The Sport Turismo's second row folds forward to allow for loading larger cargo and its overall hauling capacity increases by 1.8 cubic feet to a total of 49 cubes.

Porsche says to expect the 2018 Panamera Sport Turismo in American dealers by the end of the year, with prices ranging from $97,250 for the Panamera 4 Sport Turismo to $105,050 for the 4 E-Hybrid, $110,250 for the 4S, and $155,050 for the Turbo. While Porsche hasn't announced pricing for its 2018 Panamera line, that starting price runs about $8,000 above a 2017 Panamera 4.

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